update heroku to use pm2

Procfile

@@ -1 +1 @@
-web: node app.js
+web: node pm2-main.js

package.json

@@ -28,7 +28,6 @@
     "express": "^4.13.3",
     "express-sequelize-session": "^0.4.0",
     "express-session": "^1.12.1",
-    "forever": "latest",
     "glob": "^6.0.1",
     "grunt": "^0.4.5",
     "grunt-cli": "^0.1.13",
@@ -48,6 +47,7 @@
     "passport-local": "^1.0.0",
     "passport-twitter": "^1.0.3",
     "pg": "^4.4.3",
+    "pm2": "^1.0.0",
     "proxyquire": "^1.7.3",
     "sequelize": "^3.13.0",
     "serve-favicon": "^2.3.0",

pm2-main.js

@@ -0,0 +1,35 @@
+var pm2 = require('pm2');
+
+var instances = process.env.WEB_CONCURRENCY || 1; // Set by Heroku or 1 (set -1 to scale to max cpu core - 1)
+var maxMemory = process.env.WEB_MEMORY || 512;    // 512 is the maximum free Dyno memory on Heroku
+
+pm2.connect(function() {
+    pm2.start({
+        script    : 'app.js',
+        name      : 'msr',                // ----> THESE ATTRIBUTES ARE OPTIONAL:
+        exec_mode : 'cluster',               // set to 'cluster' for cluster execution
+        instances : instances,
+        max_memory_restart : maxMemory + 'M',   // Auto restart if process taking more than XXmo
+        env: {                            // If needed declare some environment variables
+            "NODE_ENV": "production"
+        }
+    }, function(err) {
+        if (err) return console.error('Error while launching applications', err.stack || err);
+        console.log('PM2 and application has been successfully started');
+
+        // Display logs in standard output
+        pm2.launchBus(function(err, bus) {
+            console.log('[PM2] Log streaming started');
+
+            bus.on('log:out', function(packet) {
+                console.log('[App:%s] %s', packet.process.name, packet.data);
+            });
+
+            bus.on('log:err', function(packet) {
+                console.error('[App:%s][Err] %s', packet.process.name, packet.data);
+            });
+        });
+
+    });
+});
+